Background: The role of immunosurveillance in the fight against cancer is well known. In addition, cancer patients have been reported to have an impaired immune function. In patients with esophageal cancer, however, the relationship between the immunological parameters of the host and their survival has not yet been evaluated fully.
Materials and methods: Of 103 patients with esophageal cancer who underwent esophagectomy, lymphocyte subsets (CD4+ and CD8+), the PHA response, and natural killer cell (NK) activity were all assessed in relation to clinicopathological features and the prognostic significance was evaluated using both a univariate and multivariate analysis.
Results: The CD4+/CD8+ ratio in 58 (56%) patients was higher than the mean of the control, while the PHA response and NK activity in 74 (72%) and 70 (68%) patients, respectively, were lower than 1 SD below the mean of the control. None of these three parameters demonstrated a low value in 5 patients, while 1, 2 and 3 parameters showed a low value in 28, 49 and 21 patients, respectively. The survival rate of the patients with low values in all of three of these parameters was significantly worse than that for the patients in whom the number of low parameters was less than two. A multivariate analysis revealed that tumor invasion and the number of low values in these parameters were independently significant prognostic factors.
Conclusions: This survival analysis revealed that low values in the CD4+/CD8+ ratio, the PHA response, and the NK activity will help predict a poor prognosis in patients with esophageal cancer.